docs: def all(self):
          """
          This method retrieve an iterator with all the available types.
  
          return: iterator of crossref document types
  
          Example:
              >>> from crossref.restful import Types
              >>> types = Types()
              >>> [i for i in types.all()]
              [{'label': 'Book Section', 'id': 'book-section'},
              {'label': 'Monograph', 'id': 'monograph'},
              {'label': 'Report', 'id': 'report'},
              {'label': 'Book Track', 'id': 'book-track'},
              {'label': 'Journal Article', 'id': 'journal-article'},
              {'label': 'Part', 'id': 'book-part'},
              ...
              }]
          """
          request_url = build_url_endpoint(self.ENDPOINT, self.context)
          request_params = dict(self.request_params)
  
          result = self.do_http_request(
              'get',
              request_url,
              data=request_params,
              custom_header=str(self.etiquette)
          )
  
          if result.status_code == 404:
              raise StopIteration()
  
          result = result.json()
  
          for item in result['message']['items']:
              yield item